It has been well established that there are clinical benefits to lowering total plasma cholesterol and low density lipoprotein (LDL) cholesterol concentrations to reduce coronary heart disease (CHD). This study is a comparison of atorvastatin and simvastatin, two drugs from the hydroxyl methyl glutaryl CoA (HMG CoA) reductase inhibitor or statin class of lipid lowering drugs. Patients in the study will be evaluated in groups based on the number of risk factors they have for CHD: 1 or no risk factors, 2 or more, or documented CHD. The purpose of the study is to evaluate the effect of these two drugs in lowering total cholesterol, LDL cholesterol and triglyceride levels in patients with and without Type II Diabetes who have mixed dyslipidemia. The primary efficacy parameter is the percent of patients who achieve the National Cholesterol Education Program (NCEP) goal for LDL cholesterol at the starting dose of the medication. Secondary efficacy parameters include the percent of people by CHD/PVD risk factor category who achieve the NCEP goal for LDL cholesterol for the initial dose of medication and after one year of treatment.